Nintex Workflow: Testing For an Attachment on a Form

Hi Folks,

My list has the typical Attachments field but my form has a few attachment controls. In a workflow, I want to test to see if the attachment control named "attch_Itinerary" has an itinerary (or any attachment) loaded into it. In the screenshot below, you can see 3 different attachment controls but I want to only test one of them excluding the others. Is there a way to do that?